function field_profile()
clear; clc;
[B]=textread('Bt_aa.DAT');
la=length(B);
t=0;
for n=1:la
    t=t+B(n,1);
    
end
t/60
n=1:length(B);
plot(B(:,1),B(:,2),'-r')
title('Field switching profile');
xlabel('Time t (second)');
ylabel('Magnetic field B(t) (Tesla)');
end
